BELEM, Brazil -- A Brazilian farmer has been convicted of ordering the death of a nun working in the Amazon as an activist for laborers and the landless.

Vitalmiro Bastos de Moura was sentenced to 30 years in prison, Estado de Sao Paulo reported Wednesday.

The U.S. born Stang, who was 73 at the time of her death, was a long-time activist in the Amazon for workers' rights and the environment. Local ranchers and loggers had repeatedly threatened her over the years.

The family of Stang -- who was originally from Dayton, Ohio -- has maintained that justice wouldn't be served until those who ordered her death were convicted of the crime.